1. Field of the Invention
The present invention relates to a device and method for monitoring a voltage supply for a vehicle system.
2. Description of the Related Art
For example, a control unit and a method for controlling occupant protection means for a vehicle are described in published Unexamined German Patent Application published German patent application document DE 10 2008 012 896 A1. The described control unit includes at least two semiconductor components which control the occupant protection means. The semiconductor components provide supply voltages for the control unit, the two semiconductor components monitoring in one direction with regard to the supply voltages. The two semiconductor components carry out a joint reset operation for the control unit as a function of the monitoring of the supply voltages. When all supply voltages are within predefined value ranges, a reset input at the control unit may be enabled, and the control unit may correctly operate with the supply voltages.
German Patent DE 101 27 54 B4, for example, describes a method for monitoring a voltage supply of a control unit in a motor vehicle. In the described method, when an error is recognized for voltages present which are generated by the supply module in the control unit, a supply module interrupts the particular function of components of the control unit via a reset line. In addition, the voltages are monitored for errors via ranges and default values. Furthermore, a test of the reset line of the control unit is initiated, the supply module then interrupting the function of components with periodic pulses for a predefined period via the reset line, and a processor counting the time between the interruptions in order to monitor the functionality of the reset line.